Textile treatment method and apparatus

ABSTRACT

Textile yarns or strands are heated, as by contact with hot rolls, and if undrawn are also drawn by roll contact, and then are compressively crimped.

O Unlted States Patent 11 1 1111 3,781,952 Stanley Jan. 1, 1974 [5TEXTILE TREATMENT METHOD AND 349,338, March 4, 1964, Pat. NO. 3,348,283.

APPARATUS [76] inventor: Robert Stanley, 620 Meadowvale [52] U.S. Cl.28/l.6, 28/72.14 Ln Media Pa 19063 [Sl] Int. Cl. D02g 1/12 [58] Field ofSearch 28/l.6, 62, 71.3, [22] Filed: July 31, 1969 28/72.14

21 Appl. NO.I 846,457

[56] References Cited Related U.S. Application Data UNITED STATESPATENTS [63] Continuation-impart of Ser. Nos. 7l7,882, April I,

968. PM 3500519 and sen No 680,851, 2,611,923 9 1952 Huine 28/62X Nov.6, 1967, Pat. NO. 3,518,733, and Ser. N0. 219141810 '2/1959 P"! 28/1-6 X684,230, Nov. 20, 1967, and say. NO. 678,428, 061. 29491659 8/1960 cums2 1967 and Ser. No 606420v Dec. 30, 1966 and 3,152,379 10/1964 Osban28/1.6 S NO. 35 3 June 9, 1969, Said Sal. No 3,174,208 3/[965 SalIO et3].... 27/72.i4

d S N 7 4 0 each is a Satterwhite Primary Examiner-Louis K. RimrodtAtt0rneyMcClure, Weiser & Millman ABSTRACT Textile yarns or strands areheated, as by contact with hot rolls, and if undrawn are also drawn byroll contact, and then are compressively crimped.

8 Claims, 15 Drawing Figures PAIENIEBJAN 11914 SHEET 2 BF 3 -vvI--TEXTILE TREATMENT METHOD AND APPARATUS This application is acontinuation-in-part of each of my following (parentheticallyenumerated) pending applications, each of which is listed with referenceto previously copending applications and their predecessor applicationswith which there was continuity and the benefits of all of which areclaimed for this application:

0. Ser. No. 717,882 filed 1 Apr. 1968, now U.S. Pat. No. 3,500,519,which was continuation-in-part of Ser. No. 600,986 filed 12 Dec. 1966and subsequently abandoned; and Ser. No. 680,851 filed 6 Nov. 1967 andnow U.S. Pat. No. 3,518,733.

i. Ser. No. 684,230 filed Nov. 1967 and (ii) Ser. No. 678,428 filed 26Oct. 1967, both as continuations-in-part of Ser. No. 302,758 filed 31July 1963 and now U.S. Pat. No. 3,376,622, which was in pertinent part acontinuation of subsequently abandoned Ser. No. 216,524 filed 13 Aug.1962; and

iii. Ser. No. 606,420 filed 30 Dec. 1966, as a continuation-in-part ofSer. No. 386,489 filed 31 July 1964 and now U.S. Pat. No. 3,317,977,which was in pertinent part a continuation of Ser. No. 216,447 filed 13Aug. 1962 and-now U.S. Pat. No. 3,145,947; and

iv. Ser. No. 835,883 filed 9 June 1969 as a continuation-in-part ofsubsequently abandoned Ser. No. 650,762 filed 3 July 1967, which was inpertinent part a continuation of Ser. No. 349,338 filed 4 Mar. 1964 andnow U.S. Pat. No. 3,348,283.

This invention relates to treatment of textile yarns or strands,including heating pretreatment and optional drawing to increased lengthfollowed by compressive crimping thereof.

A primary object of the present invention is enhanced uniformity incompressive crimping of textile yarns or strands.

Another object is improvement in configuration or stability (or both) ofcrimp therein.

A further object is provision of a combined drawing and crimping processtherefor.

Other objects of this invention, together with means and methods forattaining the various objects, will be apparent from the followingdescription and the accompanying diagrams.

FIG. 1 is a schematic representation of the processing of a textile yarnor strand according to this invention;

FIG. 2 is a schematic representation, largely in block form, of suchprocessing;

FIG. 3 is a side elevation of means for supplying a textile yarn orstrand for such processing from an illustrated alternative sourcepackage thereof;

FIG. 4 is a front elevation of the components of FIG. 3 taken at aninclination as indicated at lVlV; and

FIG. 5 is a schematic representation of a stuffercrim per usefulaccording to preceding views, with especial reference to FIG. 2;

FIGS. 6A, 6B, and 6C are schematic representations of stuffer crimpersso useful and including movable impeding or back-pressure components;

FIG. 7 is a front elevation, partly cut away, of such a stuffer crimperin further detail and showing a yarn or strand passing therethrough;

FIG. 8 is a side elevation ofthe stuffer crimper shown in FIG. 6; and

FIG. 9 is a plan view of the stuffer crimper of the preceding views,less the yarnor strand.

FIG. 10 is a perspective view somewhat stylized, of an arrangement ofdrawing components useful according to this invention;

FIG. 11 is a perspective view of an alternative arrangement of drawingcomponents similarly useful;

FIG. 12 is a schematic representation of electrical circuitry andrelated components useful according to this invention; and

FIG. 13 is a schematic representation of other electrical circuitry andrelated components useful therein.

In general, the objects of the present invention are accomplished, inthe treatment of textile yarns or strands, by heating the same withoutsliding contact with any solid heating surface, and then compressivelycrimping the same, as in a stuffer crimper having a temporarilyconfining chamber defining an accumulating or bunching zone therefor. Ifdrawable to increased length, whether undrawn or only partially drawn,the yarns or strands are passed in essentially non-slipping contact withsuccessive sets of rolls rotating at successively increasing surfacespeeds and are so heated as to ensure drawing as well as crimpingthereof, after which they are cooled or allowed to cool.

FIG. 1 shows, largely schematically, strand l0 unwinding over the end ofconical package 11 and thereby acquiring a slight twist, to be withdrawnlinearly or lengthwise and be so advanced or forwarded through guide 12and successive pairs of rolls l3, l3 and 15, 15. Enclosure 14, which maybe heated, as by hot-air convection or by an electrical radiant-heatingelement (not shown) or which may simply constitute a barrier to loss ofheat to the atmosphere from the yarn or strand, which is readily heatedby the rolls, extends thereabout between the respective sets of rollsand may extend to or even about the rolls, if desired.

Although not illustrated, methods and means for heating the rolls,preferably internally, will come readily to the mind ofa person skilledin the art: e.g., by circulation of heated fluid therein or byelectrical means as disclosed in my U.S. Pat. No. 3,111,740, especiallyFIGS. 6-to 8 and the description thereof. Traversing means 16,optionally used for assisting in distribution of the yarn or strandalong the nip of feed rolls 17, 17', follows the second pair of rollsand precedes the feed rolls at the entrance to stuffing chamber 18, towhich the yarn or strand proceeds directly from rolls 15, 15.Compressively crimped yarn or strand 10 (so designated to distinguish itfrom the uncrimped starting form) is wound up from the exit of thechamber past aftertreating means 19, in which it is adjusted in tension(such as in my U.S. Pat. No. 3,500,5 19) or temperature (or both) andonto traverse-wound package 21 by selftraversing drive roll 20 rotatingin contact therewith.

FIG. 2 shows schematically the location of heating, intermediate, andcooling zones, represented in block form, between the supply and windupcomponents of FIG. 1. After leaving guide 12, yarn or strand 10 passessuccessively through Heating Zone 24, which has initial and finalboundaries A and B; Intermediate Zone 25, which has initial and finalboundaries B and C; and Cooling Zone 26, which has initial and finalboundaries C and D; after which it is wound by roll 20 onto package 21as previously mentioned. Location W in the heating zone, locations X andY in the intermediate zone, and location Z in the cooling zone arecharacterized further below.

It will be understood that conical package 11 may be replaced by anysuitable source of yarn or strand 10, such as traverse-wound package 31shown in side and front (slightly inclined) elevation, respectively, inFIGS. 3 and 4. This package is mounted for rotation on axle 32 suitablysupported. Mounted on axes parallel thereto are roll 33 located aboveand behind the package; roll 34 located below and behind the package,and roller guide 35 located ahead of and below the package and centeredfrom end to end thereof. As yarn or strand 10 unreels (without acquiringany twist) from package 31 and about rolls 33 and 34 and roller guide35, it traverses the successive rolls to a successively decreasingextent as compared with the full traverse thereof on the package, asindicated by the broken lines. This arrangement smoothes out the tensionchanges characteristic ofa yarn or strand supplied from a traverse-woundpackage, thereby facilitating uniformity of further treatment andconsequent elimination of objectionable irregularities in the resultingproduct.

FIG. schematically locates feed rolls 17, 17 and stuffing chamber 18with respect to the zones indicated in FIG. 2. Location X in theintermediate zone is denoted as coincident with the roll axes, andlocation Y (also in the intermediate zone) as at or near the end of thechamber, wherever the yarn or strand is released from the impeding forceor back-pressure that applies crimping stress thereto.

FIGS. 6A, 6B, and 6C show, also schematically, three conventional typesof stuffing (or stuffer box) chambers 18, with particular reference toimpeding or backpressure elements for the yarn or strand therein, in theorder of their development: gravity-actuated or springloaded gate 37 inFIG. 6A; reciprocating plunger 38, without or with a centrallongitudinal bore, in FIG. 6B; and unidirectionally movable or movingwheel (which also comprehends belts, etc.) or gear-like element 39 inFIG. 6C. Each of these types of impeding means applies back-pressure tocrimped yarn or strand seeking to escape from. the chamber, or from thatpart thereof in which it is. under crimping stress, as the feed rolls(shown previously) or equivalent means forcibly stuff more uncrimpedyarn or strand 10 into the chamber. Examples of these respective typesmay be found in U.S. Pat. Nos. 2,686,339, 2,734,229, and 3,027,619;hence, the omission of most details of their construction. The rate ofwindup or other withdrawal of crimped yarn or strand 10 may besynchronized in timed relation to the rate of feed of uncrimped yarn ofstrand 10 into the stuffing chamber as disclosed in my U.S. Pat. Nos.3,280,444 and 3,388,440, especially FIGS. 4 to 9 thereof and the relateddescription, if de sired.

FIGS. 7, 8, and 9 show in front elevation, side elevation, and top plan,respectively, stuffer crimper 40 embodying feed rolls 17, I7 andstuffing chamber 18, as well as related components. No impeding element,such as previously illustrated and described, is included in this view,it being understood that one may be used therewith, if desired;alternatively, lateral confinement by and friction with the sidewalls ofthe stuffing chamber may suffice, as disclosed in my aforementioned U.S.Pat. Nos. 3,279,025 and 3,386,142. As shown in FIG. 7, part of the frontwall of stuffing chamber I8 is cut away to reveal crimped strand I0inside chamber bore 28 being withdrawn (as by roll of FIG. I) from theleading or head end of accumulation 10a thereof in the form of a bunchedor compressed wad or plug in the lower part of the chamber and whichotherwise would extend at lesat to any impeding element used therewith.

Also shown in FIGS. 7, 8, and 9 is frame 42, which supports stuffingchamber 18 and related components and which has an inverted U-shape asviewed from the side (FIG. 8). Shafts 47, 47 for respective feed rolls17, 17 are journaled in the front and rear walls of the frame and haveintermeshing gears 57, 57 thereon behind the rear wall of the frame.Shaft 47 also has driven pulley 49 affixed thereon. Motor 51 on thehorizontal upper surface of the frame has shaft 52 on which is drivepulley 53. Belt 54 interconnects pulleys 53 and 49 to transmitrotational force from the motor to the gears, shafts, and the feed rollsthemselves. Also shown is roll 17 carried on stub shaft 47" parallel toand aligned with the feed rolls and their shafts, with the peripheralsurface of roll 17" contiguous with the peripheral surface of feed roll17 on one side thereof as is the peripheral surface of feed roll 17' onthe opposite side. The tapered entrance of the stuffing chamber, shownschematically in earlier views, extends within the bight of the feedrolls but is hidden from view by the lower end of the chamber, the frontand rear walls of which overlap portions of the front and rear faces ofthe rolls as far as the roll nip so as to ensure that the infed yarn orstrand enters the chamber rather than possibly escaping therefrom.

The stuffing chamber and other rigid apparatus elements may be made ofsteel or other durable material. If desired, the inside wall ofthechamber may be coated (e.g., with tetrafluoroethylene) to reduce thecoefficient of friction, in which event the chamber should be lengthenedaccordingly. In the absence of any impeding element a chamber length ofabout a yard or meter, with a bore width of about a quarter inch or acentimeter for use with yarns or strands of about 10 to denier, hasproved suitable for nylon and similar textile materials, such as willcome readily to the mind of a person skilled in the textile arts.

Prominent among suitable textile compositions are the nylons(polycarbonamides), e.g., 66 nylon (i.e., polyhexamethylene adipamide),also 6-nylon, ll nylon, 610 nylon, and fiber-forming copolymers thereof,including terpolymers. Other suitable polymeric mate rials for yarns orstrands to be treated according to this invention include most of thethermoplastic fiberforming materials, such as polyhydrocarbons (e.g.,polyethylene, polypropylene), polyesters (e.g., polyethyleneterephthalate), polyacrylonitrile and copolymers of acrylonitrile withother vinyl compounds, also copolymers of vinyl chloride and vinylidenechloride, and polyurethanes. This list is simply exemplary and is notintended to be exhaustive of suitable compositions, most or all of whichare thermoplastic.

According to this invention, thus far considered, yarn or strand 10 iswithdrawn from a suitable source of supply, then is heated by or betweensuccessive sets of rolls without sliding contact with a heated solidsurface and is stuffed while hot into a confining chamber, within whichit is subjected to longitudinal compression to buckle it into crimpedconfiguration and from which it is then withdrawn and usually wound up.The entering yarn or strand usually is fed or driven into the noll nipand the juxtaposed chamber entrance from along the common internaltangent thereto extended therefrom,

as shown in solid in FIG. 7. Where it is desired to grip the yarn orstrand over a greater distance than is provided by the nip of feed rolls17, 17 it may proceed along the alternative path, shown there in brokenlines beginning at the left of the view and extending about a quadrantor so of added roll 17", downward through the nip of rolls 17" and 17,about the lower half of roll 17, and then upward to the nip of rolls 17,17 and the chamber entrance.

The heated yarn or strand enters the stuffing chamber at desiredcrimping temperature, which is depen dent upon the composition, denier,processing rate, time in the chamber, etc., and often is within therange of 150 to 350F. So long as it is under substantial crimpingcompression it preferably is kept under adiabatic conditions, or withaddition (or subtraction) of heat such as may be required to compensatefor heat loss (or'frictional heating) and thereby to maintainessentially constant-temperature conditions until completion ofcrimping. Then heat is removed from the crimped yarn or strand in thecooling zone to bring it to approximately room temperature, as byventilation with cool air or otherwise, it being recognized that thecrimped yarn or strand probably will have cooled somewhat (e.g., toabout 120F.) before reaching the stuffing chamber exit. Such coolingprevents undesired deformation that might occur in hot yarn or strandwound into package form.

Although the diagrams illustrate only what appears to be a monofilament,it will be understood that yarns or strands suited for treatmentaccording to this invention include also multifilaments and compositestructures comprising shorter lengths (e.g., staple) than are usuallyconsidered to be continuous filaments. Although many, if not all, of thesuitable compositions are drawable to increased length, usuallyresulting in orientation of their component macromoleculeslongitudinally, detailed consideration of drawability of the yarns orstrands being treated has been deferred to here in this application inthe interest of orderliness and simplicity of description andillustration.

It has been customary to accomplish such orientation of drawable textileyarns or strands by a drawing process removed or unrelated in locationand time (being prior, usually long prior) with respect to whatevercrimping process is applied thereto to enhance their bulk, cover, hand,texture, etc. Most crimping processes tend to extend the subject yarn orstrand axially while deforming it transversely of the longitudinal axis,as in edge-crimping, gear-crimping, jet-crimping, and twist-crimping.While there might be reason to believe that it would be feasible toperform such an extensional crimping process soon after drawing, astogether with performance of one or more additional steps, the same isnot true of a compressive or compressional crimping process, such asstuffer crimping.

The general view is that the usual time lag between drawing and stuffercrimping presumably permits the condition of increased orientation andlength to become desirably stabilized. There is a greater contradictioninvolved in first extending a yarn or strand longitudinally and thenimmediately compressing it longitudi-.

nally than there is in extending it in both a drawing step and afollowing crimping step. However, the present invention provides adrawing step followed by a compressive crimping step'without appreciabletime inter vening, i.e., as a draw-crimping process.

FIGS. 10 and 11 show in perspective two suitable arrangements for sodrawing yarns or strands to increased length directly before crimping,each such arrangement consisting of two sets of rolls variously arrangedbut flanking a draw pin such as is optionally useful in localizing thedraw. It will be understood that at least one of the rolls in each ofthese two sets is driven by suitable motive means (not shown) and thatall the rolls within each set rotate at constant speed, whether drivendirectly by the motive means or indirectly by contact (essentiallynon-slipping) with one another. The surface speed of the rolls in thesecond or forwarding set is sufficiently greater than the speed of therolls in the first or input set to draw the yarn or strand to desiredincreased length therebetween. The draw pin does not rotate but is fixedso as to snub the strand passing about it. The pin may, but need not, beheated by any conventional means (e.g., electrically or by steam,preferably supplied internally) in accordance with the art of textiledrawing.

In FIG. 10, a pair of input rolls 61, 62 spaced from one another ingodet fashion precede draw pin 65, and similar pair of output orforwarding rolls 68, 69 follow the draw pin. Yarn or strand 10 passessuccessively about the input pair of rolls as a group, about the drawpin, and about the output pair of rolls as a group. Additional wrapsabout the respective pairs of rolls may be employed if required foressentially non-slipping contact therewith. See my U.S. Pat. No.3,518,733 for a similar arrangement in which the spacer or separatorrolls are smaller than the godet rolls.

In FIG. 11, input rolls 7!, 72, 73 arranged in a horizontal three-rollstack, and output rolls 77, 78, 79 are similarly arranged. Thus, rolls71 and 73 flank and are contiguous with roll 72, while rolls 77 and 79are similarly arranged with respect to roll 78. Yarn or strand passesabout an upper quadrant of roll 71, through the nip between rolls 71 and72, about the lower half of roll 72, through the nip between rolls 72and 73, and over an upper quadrant of roll 73 in its path to draw pin75. From the draw pin it proceeds in like manner about a quadrant ofroll 77, through the nip between rolls 77 and 78, halfway about roll 78,through the nip between rolls 78 and 79 and onward to a stuffer crimper,previously shown. Because the yarn or strand is gripped by successiveroll nips as well as by frictional contact with portions of the rollsurfaces, complete or multiple wraps are not required to ensureessentially nonslipping roll contact.

It will be understood that either arrangement of draw rolls may besubstituted for pairs of rolls l3, l3 and l5, 15' shown in FIG. 1.Heating enclosure 14 may be retained or not, as desired, but in eitherevent it is most convenient and effective to heat one or both sets ofrolls, possibly in addition to (or instead of) heating the draw pin.Heating the first set of rolls preheats the strand for drawing,rendering it generally easier to draw, and incidentally preheating itfor crimping, while heating the second set of rolls in addition thereto,if desired, at least sufficiently to prevent the drawn strand fromcooling in the interim (however brief) before crimping, is conducive toa steady and high degree of crimping. Of course, as can be seen readilyfrom the prior discussion hereinabove, even heating only the second setof rolls is often beneficial to the degree of crimp. Althougn notillustrated or further described herein, suitable methods and means forheating the draw rolls, preferably internally, will be apparent, such asby use of heated fluid or electrical resistance elements as mentionedabove in the discussion of heating one or more of rolls 13, 13' and l5,15'.

The relative speeds of the output and input rolls determine the drawratio, which essentially determines the relationship of the new lengthof the drawn strand to its former or undrawn length. Customary drawratios are in the range from about 2 to 6X, although sometimes higherdraw ratios may be employed and lower draw ratios may be employed inindividual stages of multiple-stage drawing processes. A common drawratio for 66 nylon is 4X, corresponding to an output/input speed ratioof4 to l. Practicable processing speeds are undergoing continualincrease and often are in the vicinity of a thousand yards or meters perminute into the crimping apparatus, but somewhat slower or faster speedsmay be employed. The speed at which the strand is fed into the crimperoften coincides with the output speed from the drawing zone, and in thatevent one or more of the crimper feed rolls may be combined with (orreplaced by) one or more of the output draw rolls. For example, outputdraw rolls 77, 78, 79 of the draw system of FIG. 11 may coincide withrolls 17", 17, 17 of the stuffer crimper of H6. 7, using the alternativepath (broken lines) for the yarn or strand to be crimped. Such anarrangement further maintains the desired elevated temperature thereofand continuity of treatment without appreciable intervening delay ortime lag.

FIG. l2 shows schematically suitable electrical circuitry and relatedcomponents useful in assuring the desired heating and control thereof.Heating region 81, shown in block form, may constitute (or be part of)Heating Zone 24. Electrical potential E1 provides, via pair of leads 84,the input to electrical bridge 82, which may be a simple Wheatstonebridge (or a more complex type) provided with resistors (or othersuitable impedance elements) Rl,-R2, R3, and R4 in its various arms:resistor R3 being a thermistor having pair of leads 83 and being locatedin region 81 to sense the temperature thereof, and the other resistorsbeing inappreciably susceptible to resistance change with variation intemperature (or being maintained at constant temperature). The bridgeoutput is transmitted via pair of leads 85 to Controller 86, which issupplied with electrical potential E2 via pair of leads 87 and whichcontrols the temperature of region 81, in response to the bridge output,by means of heating element RH located in that region and connected tothe controller via leads 88.

lnstead of being a resistor the heating element may be suitable radiant(or other) heating means and the leads thereto be suitable piping, thecontroller controlling the flow of heating fluid through the piping inconventional manner as it can control the flow of heating electricalcurrent. Further details of the controller and its connection into thecircuit are omitted for simplicity, being obvious to persons having anunderstanding of the pertinent art.

FIG. 13 shows, also schematically, cooling region 91, which mayconstitute (or by part of) Cooling Zone 26. It is provided withtemperature-sensitive resistor or thermistor R5 located therein andhaving pair of leads 93 to a bridge (not shown) by analogy to thesimilar elements ofthe immediately preceding view. Cooling element RCalso located in region 91 has pair of leads 98 to a controller (notshown), the further analogy with the apparatus of FIG. 12 beingapparent. The cooling element may be either a thermoelectric element ora refrigerating coil (in which instance leads 98 would be piping), forexample. As suggested above a cooling element might be useful inIntermediate Zone 25 as well, such as near (inside) the entrance to thestuffing chamber where the applied longitudinal compression andresulting buckling or columnar collapse of the yarn or strand generatesundesired heat, as may friction with the feed rolls or the chamberentrance itself.

With suitable insulation of the Heating, Intermediate, and CoolingZones, such apparatus permits accurate control of the temperaturethereof. The respective zones should be sufficiently large, as comparedwith the rate of travel of the strand therethrough, to hold the strandfor a long enough time to have the desired effect upon it.Temperature-sensing means may be provided at locations W, X, Y, Z, assuggested above, or at other convenient locations to ensure accuratedetermination of temperature, together with temperature-controllingmeans as may be required for the desired temperature control. Insulationof the Intermediate Zone, which contains the crimping means, from theother two zones may suffice to ensure adiabatic conditions therein.However, if that does not suffice to maintain the strand at essentiallyconstant temperature therein, and especially while it is under crimpingstress, one or more controllers (with heating or cooling elements, orboth) may be-employed as in the other two zones.

While various embodiments of this invention have been disclosed, othermodifications may be made, as by adding, combining, or subdividing partsor steps, while retaining significant benefits and advantages of theinvention, some of which have been mentioned and others of which willbecome apparent to those undertaking to practice the invention inaccordance with the foregoing teaching. The invention itself is definedin the following claims.

The claimed invention is:

l. A method for treating thermoplastic yarn comprising the steps oftaking the yarn from a supply, advancing the yarn around a rollerarrangement, heating the yarn as it travels around said rollerarrangement, advancing the heated yarn away from the roller arrangementat a faster rate than the rate at which the yarn travels around saidroller arrangement and thereby drawing the heated yarn, driving thedrawn yarn into a stuffer box crimping chamber while said drawn yarn isstill in a heated condition and thereby crimping the yarn and forming aplug of crimped yarn, and removing the crimped yarn from the head of theplug.

2. Apparatus for treating thermoplastic yarn comprising means fordrawing the yarn, means for crimping the drawn yarn by longitudinalcompression and means for winding the crimped yarn, said drawing meanscomprising a roller arrangement and means for heating the yarn and meansfor advancing the heated yarn away from said roller arrangement, saidheating means being arranged to heat the yarn as it travels around saidroller arrangement and said means for advancing the yarn being adaptedto advance the heated yarn away from said roller arrangement at a fasterrate than the rate at which the yarn travels around said rollerarrangement, said crimping means including a chamber defining a yarnbunching zone for forming a plug of crimped yarn and means for drivingthe drawn yarn into said chamher while the yarn is still in a heatedcondition from said drawing means, said winding means being arranged towind the drawn and crimped yarn from the head of the plug thereof formedby the said chamber.

3. Apparatus for treating thermoplastic yarn comprising means fordrawing the yarn, means for crimping the drawn yarn by longitudinalcompression and means for winding the crimped yarn, said drawing meanscomprising a roller arrangement and means for heating the yarn and meansfor advancing the heated yarn away from said roller arrangement, saidroller arrangement including a driven roller having a peripheral surfacein contact with which the yarn travels, said heating means beingarranged to heat the yarn as it travels with said peripheral surface andsaid means for advancing the heated yarn being adapted to advance theheated yarn away from said roller arrangement at a faster rate than therate at which the yarn travels with said peripheral surface, saidcrimping means including a chamber defining a yarn bunching zone forforming a plug of crimped yarn and means for driving the drawn yarn intosaid chamber while the yarn is still in a heated condition from saiddrawing means, said winding means being arranged to wind the drawn andcrimped yarn from the head of the plug thereof formed by the saidchamber.

4. The apparatus of claim 3 wherein said driven roller includes integralmeans for heating said peripheral surface.

5. The apparatus of claim 3 wherein said means for advancing the heatedyarn away from said roller arrangement comprises a second rollerarrangement, said second roller arrangement including a second drivenroller having a peripheral surface in contact with which the yarntravels.

6. The apparatus of claim 5 wherein said second driven roller includesintegral means for heating the peripheral surface thereof.

7. The apparatus of claim 3 wherein means are provided for varying therelative rate of speed of said driven roller and said means foradvancing the heated yarn.

8. The apparatus of claim 7, wherein the said driven roller is driven ata peripheral speed of two and onehalf times to five times slower thanthe peripheral speed of said second roller and said second roller passesthe yarn at a speed within a range including 500 meters per minute.

1. A method for treating thermoplastic yarn comprising the steps oftaking the yarn from a supply, advancing the yarn around a rollerarrangement, heating the yarn as it travels around said rollerarrangement, advancing the heated yarn away from the roller arrangementat a faster rate than the rate at which the yarn travels around saidroller arrangement and thereby drawing the heated yarn, driving thedrawn yarn into a stuffer box crimping chamber while said drawn yarn isstill in a heated condition and thereby crimping the yarn and forming aplug of crimped yarn, and removing the crimped yarn from the head of theplug.
 2. Apparatus for treating thermoplastic yarn comprising means fordrawing the yarn, means for crimping the drawn yarn by longitudinalcompression and means for winding the crimped yarn, said drawing meanscomprising a roller arrangement and means for heating the yarn and meansfor advancing the heated yarn away from said roller arrangement, saidheating means being arranged to heat the yarn as it travels around saidroller arrangement and said means for advancing the yarn being adaptedto advance the heated yarn away from said roller arrangement at a fasterrate than the rate at which the yarn travels around said rollerarrangement, said crimping means including a chamber defining a yarnbunching zone for forming a plug of crimped yarn and means for drivingthe drawn yarn into said chamber while the yarn is still in a heatedcondition from said drawing means, said winding means being arranged towind the drawn and crimped yarn from the head of the plug thereof formedby the said chamber.
 3. Apparatus for treating thermoplastic yarncomprising means for drawing the yarn, means for crimping the drawn yarnby longitudinal compression and means for winding the crimped yarn, saiddrawing means comprising a roller arrangement and means for heating theyarn and means for advancing the heated yarn away from said rollerarrangement, said roller arrangement including a driven roller having aperipheral surface in contact with which the yarn travels, said heatingmeans being arranged to heat the yarn as it travels with said peripheralsurface and said means for advancing the heated yarn being adapted toadvance the heated yarn away from said roller arrangement at a fasterrate than the rate at which the yarn travels with said peripheralsurface, said crimping means including a chamber defining a yarnbunching zone for forming a plug of crimped yarn and means for drivingthe drawn yarn into said chamber while the yarn is still in a heatedcondition from said drawing means, said winding means being arranged towind the drawn and crimped yarn from the head of the plug thereof formedby the said chamber.
 4. The apparatus of claim 3 wherein said drivenroller includes integral means for heating said peripheral surface. 5.The apparatus of claim 3 wherein said means for advancing the heatedyarn away from said roller arrangement comprises a second rollerarrangement, said second roller arrangement including a second drivenroller having a peripheral surface in contact with which the yarntravels.
 6. The apparatus of claim 5 wherein said second driven rollerincludes integral means for heating the peripheral surface thereof. 7.The apparatus of claim 3 wherein means are provided for varying therelative rate of speed of said driven roller and said means foradvancing the heated yarn.
 8. The apparatus of claim 7, wherein the saiddriven roller is driven at a peripheral speed of two and one-half timesto five times slower than the peripheral speed of said second roller andsaid second roller passes the yarn at a speed within a range including500 meters per minute.